Missile Defense Alarm System (Midas): Any of a series of unmanned U.S. military satellites developed to provide warning of surprise attacks by Soviet intercontinental Ballistic missiles (ICBM).

• 飞弹防御警报系统:一系列无人操作的美国军事卫星,发展目的在于提供苏联洲际弹道飞弹突袭的警报。